Conventionally, there are digital cameras and monitoring cameras including flash devices. As a light source of flash devices, xenon tubes have been mainly used, since such xenon tubes have short-time optical outputs and is excellent in color rendering properties.
Such flash devices are composed of a xenon tube 401, an inverter 402, an aluminum electrolytic capacitor 403, and a switch circuit 404, etc., as shown in FIG. 46. Such flash devices are configured so that the xenon tube 401 emits light by transforming an electric charge charged in the aluminum electrolytic capacitor 403 into an electric current with switching operation using the inverter 402.